Fears have been raised Blackpool’s multi-million pound sea defences may already be eroding.
Academic Peter Hughes claims a flaw in the concrete means the resort’s flagship new Spanish steps are already beginning to show signs of degradation.
He says lessons need to be learned ahead of the building of the next stage of the scheme at Anchorsholme.
But Blackpool Council has dismissed Mr Hughes’ findings, and says any damage is the result of natural forces including debris being smashed onto the defences by waves.
The defences, between South Pier and North Pier, were built at a cost of £76m with the total scheme including surface work to the headlands adding up to £100m.
Mr Hughes, 54, of Knowsley Avenue, Blackpool, has been studying the concrete used in the project since it began in 2007, for his PhD at the University of Central Lancashire in Preston.
The former technical illustrator already has a science degree in building surveying and has had several research articles published in concrete industry journals.
He told The Gazette he found bacteria in the beach sand used in the concrete and this had grown around synthetic fibres used to reinforce the concrete instead of steel traditionally used in the past.
He also found traces of algae attached to the fibres, and claims these processes have weakened the defences.
Mr Hughes said: “It makes it more susceptible to tidal impact and power washing.
“Units are already having to be repaired after only five years yet they were designed to last 100 years.
“It is the first time fibres like this have been used in a marine environment.
“I want to ensure engineers look at this before they design the sea defences at Anchorsholme. These units are being used all over the country and are going into Europe.
“They are using Blackpool as a model.”
The UK Concrete Society confirmed it has published articles about Mr Hughes’ studies of concrete, but declined to comment on his findings.
Glyn Morton, emeritus professor of environmental biology at UCLAN, said: “What he had found is the sand the actual revetments are made of has micro-organisms in it which aren’t necessarily destroyed by the concrete-making process.
“He has become quite an expert and is causing a reasonable amount of concern in the industry.”
‘We’ve no concerns over the sea wall concrete’
Blackpool Council said it had no concerns about the longevity of the new defences.
Coun Gary Coleman, cabinet member for urban development and regeneration, said: “When commissioning the concrete for the sea defences, we used a nationally recognised contractor; Tarmac, and sand from St Annes.
“The same sand is used for all Tarmac’s comparable work regionally.
“We are content that this, the composition of the structure generally and the cleaning of algae from the structure, which has been factored into our considerations throughout, has caused no issues.
“In short, we have no concerns about the composition or longevity of the concrete.
“Our officers have also heard from other industry figures who are extremely sceptical about this research.
“We must remember the structure is subject to an enormous impact from the tide, from debris in the sea, from the weather which make it almost impossible to determine the cause of the minor damage which is pictured. Our award-winning sea defences project has been a huge success, providing a long-lasting safeguard for the future.”